SMARCKS smart blocks and other smart block toys may respond to assembly events by making sounds and activating lights. LEGO MINDSTORM kits may allow complex configuration and use with simple programming interfaces suitable for younger users, including robots that can be built with the kit. Depending on what blocks are added to the robot as built, the robot may behave in different ways. LEGO FUSION may allow younger users to build models that are photographed and reproduced in a virtual world on a computer screen.